Anaplasmosis is a tick-borne transmitted infection. Its clinical expression include fever, cytopenia and hepatitis.This infection was initially described in United States. In Europe, its epidemiology is not well known. Some isolated cases have been diagnosed in several country, were the tick Ixodes ricinus is known to transmitted another infection :the Lyme borreliosis.The purpose of our study is to look systematically for Anaplasmosis, in patient living in Eastern France, and presenting with compatible clinical symptoms using a new diagnosis tool : PCR in blood samples. So we will have new data about epidemiology in our country and the clinical symptoms that are associated with Anaplasmosis.